From the screen where Kito is working on the airplane, exit to the bottom right. The next screen will have 2 exits, to the right and in the middle next to the power box you interacted with at the beginning. Take the middle exit there, and the next screen will have an elevator that’s unavailable to you.
Directly under the sign and next to the elevator door, will be graffiti. Interact with it for some dialogue, and an achievement.